Gastric juice is known to have phospholipase A2 catalytic activity. Helicobacter pylori (H. pylori) has been reported to produce phospholipase A2, which is believed to hydrolyse the protective layer of gastric mucosal phospholipids and to promote mucosal damage. The current study aimed at identifying secretory phospholipase A2 subtypes (pancreatic group I phospholipase A2 and synovial-type group II phospholipase A2) in gastric juice and their relation to the presence of H. pyloriin gastric mucosal biopsies in the same individuals. Gastric juice was collected from 29 individuals during gastroscopy. Biopsies were taken from the antrum and body of the stomach to determine the H. pylori status. We found catalytically active phospholipase A2 and both group I and group II phospholipases A2 in the gastric juice samples. The catalytic activity and the mass concentrations of group I and group II phospholipases A2 correlated significantly with the pH value in gastric juice. The gastric juice of H. pylori positive individuals did not contain higher amounts of phospholipases A2 than the juice of H. pylori negative individuals. Rather, the mass concentration of group II phospholipase A2 in gastric juice seemed to be somewhat lower in individuals with H. pylori infection than in uninfected individuals. The results of the current study show that both group I and group II phospholipases A2 are present in gastric juice. The main sources of phospholipases A2 in gastric juice are probably other than H. pylori.
Group II phospholipase A2 has been proposed to play an important role in the pathophysiology of inflammatory bowel diseases. This enzyme has also been linked to host defence mechanisms against bacteria. The current study aimed at measuring the mass concentrations of group II phospholipase A2 in serum and colonic mucosa of patients with Crohn's disease of different severity and of appropriate control patients without any inflammatory disease. The activity of the disease was determined by clinical factors (the simple index score) and endoscopic and histological scoring. The mass concentration of group II phospholipase A2 was measured by a time-resolved fluoroimmunoassay. The mass concentrations of group II phospholipase A2 in serum and colonic mucosa were significantly higher both in patients with active and inactive Crohn's disease when compared with controls. There was statistically significant difference in the mass concentration of group II phospholipase A2 in colonic mucosa but not in serum between inactive and active Crohn's disease. The current results indicate that the mass concentration of group II phospholipase A2 is increased in serum and colonic mucosa of patients with Crohn's disease and that the latter is associated with the degree of the inflammatory activity in the intestinal wall. These results support the idea that group II phospholipase A2 is involved in the local and generalised pathological processes of Crohn's disease.